1. From the Cardiology Division of the Department of Medicine (B.D.R., T.E., J.A.C.L.) and Departments of Radiology (E.C., D.A.B.) and Biomedical Engineering (L.P.), Johns Hopkins Medical Institutions, Baltimore, Md; Department of Epidemiology, Bloomberg School of Public Health and Hygiene (S.L.), Johns Hopkins University, Baltimore, Md; University of Minnesota, Minneapolis (M.J.-H., D.A.); UCLA, Los Angeles, Calif (S.S.); Wake-Forest University School of Medicine, Winston-Salem, NC (J.R.C.); and...